Simon Willison’s Weblog

How Zoom’s web client avoids using WebRTC (via) It turns out video conferencing app Zoom uses their own WebAssembly compiled video and audio codecs and transmits H264 over WebSockets.

Posted 18th April 2019 at 6:20 pm

Recent articles

Useful patterns for building HTML tools - 10th December 2025
Under the hood of Canada Spends with Brendan Samek - 9th December 2025
Highlights from my appearance on the Data Renegades podcast with CL Kao and Dori Wilson - 26th November 2025

websockets 20 webassembly 84

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